Does the uses of "celý" vs. "-------" correspond to the uses of "entire" vs. "all"? EDIT: I removed the monster I created.
Všechný does not exist.
celý = whole, entire...
všechen (m), všechna/všecka (f), všechno/všecko/vše (n) = all, everything, everyone...
More or less. Yes. Celý can also be translated as "whole". And you would here people say On snědl celé maso. But as in English they mean the entire piece of meat that was available.
No. Czech language often employs the concept of perfective-imperfective verb pairs. Jíst is imperfective, sníst perfective. They are somewhat similar, but they are definitely not synonyms.
As a side note, the past participle of jíst is jedl. J cannot be followed by ě.
I put "Matej has eaten all the meat again" which was marked wrong because the word meat was wrong - I assume it is some kind of glitch? Anyway I have reported it.